Combine the cubed chicken breast, teriyaki sauce, water, brown sugar, garlic, carrots, pineapple chunks, red pepper, green pepper, and water chestnuts in a large resealable freezer bag.
Squish to combine.
Thaw.
Transfer the contents of the bag to a large baking dish. Preheat the oven to 350° and bake uncovered for 50 minutes.
Serve over rice.